5.3

CVE-2026-23829

Exploit

Mailpit has SMTP Header Injection via Regex Bypass

Mailpit is an email testing tool and API for developers. Prior to version 1.28.3, Mailpit's SMTP server is vulnerable to Header Injection due to an insufficient Regular Expression used to validate `RCPT TO` and `MAIL FROM` addresses. An attacker can inject arbitrary SMTP headers (or corrupt existing ones) by including carriage return characters (`\r`) in the email address. This header injection occurs because the regex intended to filter control characters fails to exclude `\r` and `\n` when used inside a character class. Version 1.28.3 fixes this issue.
Daten sind bereitgestellt durch National Vulnerability Database (NVD)
Axllent ≫ Mailpit Version < 1.28.3
Zu dieser CVE wurde keine Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 1.44% 0.698
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
security-advisories@github.com 5.3 3.9 1.4
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
CWE-150 Improper Neutralization of Escape, Meta, or Control Sequences

The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could be interpreted as escape, meta, or control character sequences when they are sent to a downstream component.

CWE-93 Improper Neutralization of CRLF Sequences ('CRLF Injection')

The product uses CRLF (carriage return line feeds) as a special element, e.g. to separate lines or records, but it does not neutralize or incorrectly neutralizes CRLF sequences from inputs.

https://github.com/axllent/mailpit/security/advisories/GHSA-54wq-72mp-cq7c
Third Party Advisory
Exploit
Mitigation
https://github.com/axllent/mailpit/commit/36cc06c125954dec6673219dafa084e13cc14534
Patch
https://github.com/axllent/mailpit/releases/tag/v1.28.3
Product
Release Notes